1. Field of the Invention
The present invention relates generally to assuring the proper operation of programmable graphics devices, and more particularly to monitoring for corruption of the function of the graphics devices including critical data contained within the graphics devices.
2. Description of the Related Art
Traditional graphics devices have fixed functionality pipelines and can only perform the operations built into them. Modern 3D Commercial Off The Shelf (COTS) graphics devices are not fixed functionality. Their functionality is programmable. These programs cause the devices to function differently from program to program. There is presently no adequate manner provided in the prior art for deterministically assuring that the device is working properly. Requirements, design, and test documentation for these devices is sparse at best. These devices cannot be trusted to monitor and report internal errors. Assuring proper operation of these programmable graphics devices is problematic and a large roadblock when it comes to certifying these parts.
Modern graphics chips have multiple programmable stages that run small programs called “shaders”. If shader code is corrupted or the graphics device does not operate correctly when executing the shader code then erroneous visual data might be displayed on the flight displays. Therefore the unprotected shader code and the proper operation of the graphics chips must be continuously verified to be free of corruption.
As will be disclosed below, the present invention assures proper operation of these programmable graphics devices.